diff options
| author | Eric Dumazet <edumazet@google.com> | 2018-10-10 12:30:11 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-08 11:25:32 +0100 |
| commit | 7fab8b2f0c994decf580027286b97533c8b7f6fd (patch) | |
| tree | 73ddbf378159434a9e9dc34c6eaebc848c0532c3 /include/linux | |
| parent | 5f2d68b6b5a439c3223d8fa6ba20736f91fc58d8 (diff) | |
net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends
commit 88078d98d1bb085d72af8437707279e203524fa5 upstream.
After working on IP defragmentation lately, I found that some large
packets defeat CHECKSUM_COMPLETE optimization because of NIC adding
zero paddings on the last (small) fragment.
While removing the padding with pskb_trim_rcsum(), we set skb->ip_summed
to CHECKSUM_NONE, forcing a full csum validation, even if all prior
fragments had CHECKSUM_COMPLETE set.
We can instead compute the checksum of the part we are trimming,
usually smaller than the part we keep.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/skbuff.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index aa4753ae1ff2..1e734e221ea3 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2796,6 +2796,7 @@ static inline unsigned char *skb_push_rcsum(struct sk_buff *skb, return skb->data; } +int pskb_trim_rcsum_slow(struct sk_buff *skb, unsigned int len); /** * pskb_trim_rcsum - trim received skb and update checksum * @skb: buffer to trim @@ -2810,9 +2811,7 @@ static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) { if (likely(len >= skb->len)) return 0; - if (skb->ip_summed == CHECKSUM_COMPLETE) - skb->ip_summed = CHECKSUM_NONE; - return __pskb_trim(skb, len); + return pskb_trim_rcsum_slow(skb, len); } #define rb_to_skb(rb) rb_entry_safe(rb, struct sk_buff, rbnode) |